I. Field of the Invention.
This invention relates generally to the field of cutting blades for lawn and garden edgers and in particular to a bevelled edger blade which can be attached to conventional lawn and garden edgers for cutting bevelled contours on edges of lawns, gardens and related areas.
II. Description of the Prior Art.
Conventional edgers now in common use have a rotary blade that turns on a horizontal axis like a rotary lawn mower tipped on its side. Edging channels with vertical walls are cut with conventional edgers. They are useful particularly at edges of lawns and gardens at their borders with sidewalks, walkways and at their borders with each other. Previous attempts have been made to construct edgers that cut channels with a slanted wall on one side.
This provides a clear separation of areas with a neat, trimmed appearance that also prevents mixed and uneven growth at the borders. But they have not become widely used because they are too cumbersome and do not fit conveniently onto present edgers as an option to vertical-wall edging. Now such contoured edging channels are cut manually with a shovel. Much labor time is required and the shovel-cut channel is not as neat and uniform as can be cut with this invention in a small fraction of the time.
Examples of the previous edging cutters that are different from this invention for cutting bevelled channels include U.S. Pat. No. 2,555,441 granted to Hackney. The Hackney cutter had a "frustro-conical disc" with at least two blades on a conical surface. A center of a truncated end of the frustro-conical disc was rotated on a horizontal shaft with a minor diameter or optionally a major diameter facing outward for cutting outwardly sloped or inwardly sloped edging channels respectively. Another bevelled edger is described in U.S. Pat. No. 2,664,807 granted to Hedrick. Instead of a convenient blade attachable to present edging machines, the Hedrick device was a complete vehicle with its own different mechanism for controlling depth of edging cuts, a deflector for deflecting cuttings and other features which made it impossible to use on present edging machines. Still another of the different previous bevelled edgers is described in U.S. Pat. No. 2,752,813 granted to Stoeber. The Stoeber patent was limited to a compete edging and ditching machine with a particular type of frame and a rotor to which a plurality of ditch-cutting blades were attachable. Different from the present invention, none of the known prior art is a bevelled cutting blade that can be attached conveniently to present conventional edging machines.